1. Field of the Invention
The present invention relates in general to apparatus for holding a specimen, such as a laboratory animal, in a fixed position during an imaging procedure such as X-ray, CAT and CT scans, MRI and PET imaging. The invention relates in particular to such apparatus which provide for the accurate repeatable positioning of a specimen time and again within the same imaging machine or within a number of different imaging machines.
2. Description of Prior Developments
In the field of medical research and patient treatment, it is often desirable to take a series of pictures or images of an anatomical feature, such as the brain, heart, knee or other organ or musculoskeletal feature over a period of time. Doctors and researchers need to review and study such features over time to understand the development, aging and changes normally associated with such features. Doctors and researchers also need to study such features as a function of the duration of a disease or pathological condition such as cancers and tumors. Doctors and researchers also need to review and monitor physiological changes in anatomical features as a function of time due to various treatments such as pharmacological and surgical treatments.
Different imaging machines are best suited for imaging different types of anatomical features. For example, bone is generally better imaged by X-ray machines and computerized axial tomography (CAT or CT) scanning machines, while soft tissue is generally better imaged by magnetic resonance imaging (MRI) machines. Imaging techniques such as bioluminescent, fluorescent and photon emission tomography (PET) generally provide better bio-functional data while MRI and CT imaging generally provide better structural and anatomical data.
As a result of the strengths and weaknesses of the various imaging techniques, researchers have come to rely on the use of a combination of images from different imaging machines to produce compound or superimposed images which integrate the best features from each imaging technique. This multiple image technique requires a specimen to be imaged on and moved between a series of different imaging machines.
In order to produce accurate and clear composite images, the specimen must be accurately and repeatably positioned within each imaging machine to allow for the accurate coregistration of the various images. This has proved to be a difficult, labor intensive and time consuming setup, adjustment and alignment process.